Five former NFL players, each of them still living, reportedly have been diagnosed with a marker for chronic traumatic encephalopathy (CTE), the brain disease associated with dementia, memory loss and depression.

ESPN.com reported the findings of the study, which was performed at UCLA.

"I've been saying that identifying CTE in a living person is the holy grail for this disease and for us to be able make advances in treatment," Dr. Julian Bailes, co-director of NorthShore Neurological Institute in Evanston, Ill., and one of the study's co-authors, told ESPN,com. "It's not definitive, and there's a lot we still need to discover to help these people, but it's very compelling. It's a new discovery."

Evidence of CTE was recently discovered in tests done on Junior Seau, who committed suicide last May. According to ESPN.com, dozens of former players -- including 34 who played in the NFL -- have been diagnosed with neurodegenerative CTE.

Two former players were named in the report -- former Vikings linebacker Fred McNeill, now 59, and former backup quarterback Wayne Clark, now 64. Three other living players in the study were not identified by name, only current age and former position.

UCLA researchers used a brain-imaging tool, which detected a protein that causes CTE.

"The findings are preliminary -- we only had five players -- but if they hold up in future studies, this may be an opportunity to identify CTE before players have symptoms so we can develop preventative treatment," Dr. Gary W. Small, the study's lead author, was quoted as saying in the ESPN.com report.

The findings were published Tuesday in the American Journal of Geriatric Psychiatry.

If the study and future tests prove to be accurate, brain testing of active players could have a profound impact on the game. Players identified with signs of CTE could take early steps -- like retirement -- to ensure a better quality of life after football.